Clinching tools and units



July 2s, 1964 T. F. TRIB'E CLINCHING TOOLS AND UNITS l2 Sheets-Sheet 1Filed Aug. 8, 1960 July 28, 1964 T. F. TRIBE CLINCHING TOOLS AND UNITS 2Sheets-Sheet 2 Filed Aug. 8, 1960 United States Patent O 3,142,329@UNCH-UNG TOOLS AND UNITS Thomas Francis Tribe, Dudley, England,assigner of onehaif to British Federal Welder and Machine CompanyLimited Filed Aug. 8, 1960, Ser. No. 48,214 Claims priority, applicationGreat Britain Sept. 15, 1959 3 Siaims. (Cl. 153-12) This inventionconcerns tools which are hydraulically, pneumatically or mechanicallyoperated for bending the margins of sheet-metal panels and relates moreparticularly to tools for folding the margin of one panel over andaround the margin of another panel and to press the margins firmly intoengagement with each other to form a panel structure from the unitedpanels. Such a procedure (which is referred to as clinching) is adopted,for instance, in the production of sheet-metal vehicled doors whereininner and outer panels of a door are united around their marginal edgesin the manner referred to.

An object of the present invention is the provision of a clinching toolof relatively simple construction which is easy to manufacture, installand operate.

A further object is the provision of a clinching tool for folding anupstanding edge flange of a sheet-metal panel to ensure that thedimensions of the finished panel structure are accurately maintained.More particularly the invention has for one of its objects the provisionof a clinching tool in which, when the height of the upstanding flangeis less than specified, the folding over operation is performed withoutimpairment and there is little or no tendency for the upstanding flangeto be extended outwardly during flattening with consequent increase inthe overall size of the panel structure.

Yet a further object of the invention is the provision of a clinchingtool which may be used with panel structures having plane margins ormargins Which are of curved profile in directions normal to the surfaceof the structure.

For convenience it will be assumed that during the clinching operationthe panel structure is in a horizontal plane and the disposition andoperation of the several parts of the clinching tools will be describedon this assumption but it is to be understood that the sheet metal panelmay be in any other plane during clinching.

According to this invention a clinching tool comprising a member forfolding over an upstanding flange of a horizontal sheet-metal panel sothat it is acutely inclined to the surface of the panel, a member forpressing the folded-over flange towards said surface and means foractuating the presser member is characterised in that the fold-overmember is pivoted for horizontal movement towards the upstanding flange,the presser member is pivotally mounted by a parallelogram linkage forvertical movement and there is provided a mechanical connection betweensaid member, said connection being such that during the first part ofthe movement of the present member the fold-over member is actuatedthereby to fold the flange and thereafter the fold-over member iswithdrawn from the flange before the presser member engages the foldedflange.

lt is preferred that the presser member be actuated by a pneumatic ram.

The mechanical connection between the presser member and the fold-overmember is preferably a cam on the presser member and a follower on thefold-over member, the latter being urged to its non-operative positionfor engagement with the cam.

A practical application of the present invention will now be described,by way of example only, with reference to the accompanying drawingswhereof:

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FIG. l is a sectional side view of a unit comprising two clinching toolsin accordance with the present invention, and

FIG. 2 is a diagrammatic plan view of a unit comprising three clinchingtools as shown in FIG. 1.

Referring to FIG. l: the clinching unit is mounted upon the top 5 of abed or frame which supports a pad 6 of suitable shape upon the uppersurface 7 of which the panels 8 and 9 rest and to which they are securedin predetermined position by a clamp means 4 shown in raised position.

The panel 8 is generally in a horizontal plane and is pre-formed with anupstanding flange 10 around its marginal edge. The panel 9 is of top-hatsection, the marginal edge 11 of which rests upon the panel 8 within theupstanding flange 10.

Beneath the top 5 is a pneumatic ram 12 the piston rod 13 of which isconnected, at 14, to the presser member 15 of the clinching tool. Thepresser member is supported from a pedestal 16 secured to the top 5 anda pair of parallel links 17 which are pivoted to the pedestal 16 and `tothe actuator bar 18 of the member 15. The pedestal 16, the links 17 andthe actuator bar 18 constitute a parallelogram linkage.

A foot 19 is secured to the upper part of the actuator bar `18, theundersurface 20 of the foot being adapted to engage the upstandingflange 10, as later described, and to press the flange 1G downwardlyupon and against the flange 11 When the bar 18 is pulled down by the ram12. The foot 19 when moved downwardly also travels horizontally i.e.along the arcuate path 21.

A cam 26 is secured to the lower end of the actuator bar 18.

A fold-over member 23 is pivoted to shaft 24 carried by a bracket 25secured to the top 5, the member 23 being disposed between the actuatorbar 18 and the support pad 6. The fold-over member 23 has a follower 22to engage the cam 26 and there is a spring 27 which urges the member 23towards the actuator bar 18, a suitable stop (not shown) being providedto limit the extent of such movement. A finger 28 projects from theupper end of the member 23 towards the flange 10, the finger 28 havingan inclined surface 29. In. FIG. 1 the several parts of the clinchingunit are shown in full lines in the position which they occupyimmediately prior to the unit being brought into operation. When the ramis thereafter actuated the bar 18 is pulled downwardly and the cam 26engages the follower 22 with the result that the finger 28 is movedforwardly to engage the upstanding flange 10 (see the right-hand side ofFIG. l). As a consequence the flange 10 is folded to some predeterminedangle e.g. about 45 t0 the horizontal.

The actuatorbar is moved horizontally when it is drawn down and the cam26 also does so. The extent of the movement of the finger 28 is duepartly to the lift of the cam 26 and partly to the horizontal movementof the actuator bar 18.

The extent of the horizontal movement of the actuator bar 18isrdetermined by the length of the links 17. For the same verticalmovement, if the links are shorter the extent of the horizontal movementis increased and conversely if the length of Vthe links 17 is greaterthe horizontal movement of the actuator bar 18 will be less. The angleto which the flange 10 is folded over from the vertical, upstandingposition towards the horizontal position may be varied by interchanginglinks 17 of different length.

The finger 28 moves mainly in a horizontal direction (there is arelatively small vertical component of movement) and in this way it isensured that even if the flange 10 is of less height than stipulated thefold-over member 28 will adequately perform its function with the resultthat the ange will be bent over to a predetermined extent. When theflange has been bent over to the required 45 (or some other angle) thecam 26 will have moved beyond the follower 22 and the linger 28 isthereupon retracted by its spring 27. Continued downward movement of theactuator bar 1S brings the surface 20 of foot 19 into engagement withthe bentover flange 10 and the foot presses the ange down on to theflange 11. By suitable selection of the part of the path 21 at which theunder-surface 20 of the foot 19 first engages the bent-over flange 10 itmay be arranged that the foot 19 moves to a greater or lesser extent inthe horizontal direction. The arcuate path 21 will be of equal radius tothe radius of the parallel links 17 but with centre displaced from theframe pivot point of the lower link 17 by the same magnitude anddirection as the foot surface 20 is displaced from the other pivot pointof said lower link. As shown in FIG. 1 the lower link 17 is horizontaland at the plane of the work when the foot surface 20 completes itsdownward pressing operation. Thus the working range of the arcuate path21 of the foot 19 has a relatively large vertical component of directionand a relatively small horizontal component of direction which istowards the panel and flange during the overall arcuate movement of thefoot 19 theretowards. Only at the instant such operation is completedwill the foot surface be moving vertically. An advantage of this is thatthe ange 10 is pressed not only downwardly but also inwardly andtherefore any tendency for the flange 10 to be deformed outwardly (i.e.away from the edge of ange 11) is reduced or eliminated. In knownclinching units when the flange 10 is not of the required height theflange may not be folded over to the required angle in which case thepresser foot may engage the upper edge of the liange 10 and force theflange 10 downwardly and outwardly away from the flange 11. Thisproduces a panel structure which is oversize. By arranging that the foot19 moves horizontally as well as vertically such tendency is reduced.Since the extent of the horizontal movement is determined by the lengthof the links 17^ it is readily possible by interchanging links to varythe amount of the horizontal movement of the foot 19 to suit particularconditions e.g. that the flange 10 is not of the required height or theangle to which it is bent is much greater than 45.

Referring now to FIG. 2: the panel structure 8, 9 is shown as having apair of straight edges 30, 31 which are joined by a curved edge 32. Foreach of the edges 30, 31 there is a clinching tool 1S comprising apresser member and a fold-over member as described with reference toFIG. 1, a pneumatic ram 12 being provided for each tool. For the curvededge 32 there is similarly provided a clinching unit comprising themembers 19, 28 which are of correspondingly curved shape. The tool 15for the curved edge 32 is also actuated by a pneumatic ram 12.

By sub-dividing the work into a number of regions each having its ownclinching tool it is possible to determine the order in which theclinching operations will be performed-it is only necessary to operaterams 12 at dilferent times. It is also possible readily to determine thepressures at which the anges will be bent over and pressed down e.g. byapplying air at different pressures to the several rams and also therate at which these operations will be performed for instance, byregulator valves or dashpot devices. In this way it is ensured that thefinal` product is more satisfactory in size and in finish.

I claim:

1. A clinching tool for folding over an upstanding flange on ahorizontal sheet metal panel, the tool comprising a frame, a fold-overmember mounted on said frame for substantially horizontal movementtoward and away from the panel and'ange, a presser member, parallelogramlinkage means supporting said presser member on said frame for movementin an arcuate path having a relatively large vertical component ofdirection toward and away from the panel and a relatively smallhorizontal component of direction which is towards the panel and angeduring the overall arcuate movement of said presser member toward thepanel and ange, power means to actuate said presser member, resilientmeans tending to urge said fold-over member to an inoperative positionaway from the panel and flange, and cam means including one element xedto the presser' member and another element xed to the fold-over member,said elements being arranged to co-act during said arcuate movement ofsaid presser member towards the panel to force said fold-over membertoward the panel against the action of said resilient means and fold theflange to an acuate inclination to the panel and thence permit return ofsaid fold-over member by said resilient means to said inoperativeposition whereby said presser member upon continuing said arcuatemovement toward the panel may directly engage and press the inclinedange against the panel.

2. A clinching tool according to claim 1 wherein said fold-over memberis pivotally mounted on said frame for substantially horizontal arcuatemovement toward and away from the panel and ange.

3. A clinching unit for folding over an upstanding non-linear ange on ahorizontal sheet metal panel, the unit comprising a frame; a pluralityof clinching tools mounted on said frame in side-by-side relation eachof said tools comprising a fold-over member mounted on said frame forsubstantially horizontal movement toward and away from a correspondingregion of the panel and ange, a presser member, parallelogram linkagemeans supporting said presser member on said frame for movement in anarcuate path having a relatively large vertical component of directiontoward and away from said panel region and a relatively small horizontalcomponent of direction which is towards said panel and flange regionduring the overall arcuate movement of said presser member toward saidpanel and flange region, resilient means tending to urge said fold-overmember to an inoperative position away from said panel and flangeregion, and cam means including one element xed to the presser memberand another element fixed to the fold-over member, said elements beingarranged to co-act during said arcuate movement of said presser membertowards said panel region to force said fold-over member toward saidpanel region against the action of said resilient means and fold saidflange region to an acute inclination to the panel and thence permitreturn of said fold-over member by said resilient means to saidinoperative position whereby said presser member upon continuing saidarcuate movement toward the panel may directly engage and press theinclined ange against the panel at said region; and Huid pressureoperated ram means to actuate each presser member individually.

References Cited in the tile of this patent UNITED STATES PATENTS1,121,675 Slentz Dec. 22, 1914 1,701,250 Young Feb. 5, 1929 1,720,133 LeRoy July 9, 1929 1,872,670 Burns Aug. 23, 1932 2,365,803 Chambers et al.Dec. 26, 1944 2,437,157 Gregoire Mar. 2, 1948 2,536,643 Housdorfer etal. Jan. 2, 1951

1. A CLINCHING TOOL FOR FOLDING OVER AN UPSTANDING FLANGE ON AHORIZONTAL SHEET METAL PANEL, THE TOOL COMPRISING A FRAME, A FOLD-OVERMEMBER MOUNTED ON SAID FRAME FOR SUBSTANTIALLY HORIZONTAL MOVEMENTTOWARD AND AWAY FROM THE PANEL AND FLANGE, A PRESSER MEMBER,PARALLELOGRAM LINKAGE MEANS SUPPORTING SAID PRESSER MEMBER ON SAID FRAMEFOR MOVEMENT IN AN ARCUATE PATH HAVING A RELATIVELY LARGE VERTICALCOMPONENT OF DIRECTION TOWARD AND AWAY FROM THE PANEL AND A RELATIVELYSMALL HORIZONTAL COMPONENT OF DIRECTION WHICH IS TOWARDS THE PANEL ANDFLANGE DURING THE OVERALL ARCUATE MOVEMENT OF SAID PRESSER MEMBER TOWARDTHE PANEL AND FLANGE, POWER MEANS TO ACTUATE SAID PRESSER MEMBER,RESILIENT MEANS TENDING TO URGE SAID FOLD-OVER MEMBER TO AN INOPERATIVEPOSITION AWAY FROM THE PANEL AND FLANGE, AND CAM MEANS INCLUDING ONEELEMENT FIXED TO THE PRESSER MEMBER AND ANOTHER ELEMENT FIXED TO THEFOLD-OVER MEMBER, SAID ELEMENTS BEING ARRANGED TO CO-ACT DURING SAIDARCUATE MOVEMENT OF SAID PRESSER MEMBER TOWARDS THE PANEL TO FORCE SAIDFOLD-OVER MEMBER TOWARD THE PANEL AGAINST THE ACTION OF SAID RESILIENTMEANS AND FOLD THE FLANGE TO AN ACUATE INCLINATION TO THE PANEL ANDTHENCE PERMIT RETURN OF SAID FOLD-OVER MEMBER BY SAID RESILIENT MEANS TOSAID INOPERATIVE POSITION WHEREBY SAID PRESSER MEMBER UPON CONTINUINGSAID ARCUATE MOVEMENT TOWARD THE PANEL MAY DIRECTLY ENGAGE AND PRESS THEINCLINED FLANGE AGAINST THE PANEL.